1. Field of the Invention
This invention relates to immunologically active substance-glass conjugates, process for producing the same, and diagnostic reagents containing the same and process for assaying physiologically active substances using the same. More particularly, it relates to immunologically active substance-frosted glass conjugates suited for use in assaying with very high sensitivity physiologically active substances in body fluids, such as hormones and proteins, process for producing the same, diagnostic reagents containing the same and process for assaying physiologically active substances using the same.
2. Description of the Prior Art
Assaying of physiologically active substances (such as hormones and proteins) contained in body fluids (such as urine, serum), is important from the diagnostic point of view, and can be carried out either by radioimmunoassay (hereinafter abbreviated to RIA) or by enzyme-immunoassay (hereinafter abbreviated to EIA). Both RIA and EIA are based on the same principle, namely specificity of antigen-antibody reactions.
Useful assaying systems commonly used for RIA and EIA are solid phase systems using insolubilized immunologically active substances with the aid of water-insoluble carriers. Water-insoluble carriers so far used are (1) plastics such as polystyrene and polyethylene, (2) natural polymers such as sepharose and cellulose, (3) glasses, and so on. Use of plastics (such as polystyrene and polyethylene) as the water-insoluble carriers is disadvantageous, because storage stability and assay precision are unsatisfactory. Immunologically active substances bound to natural polymers such as sepharose and cellulose are flocculent or fluffy, and difficult to treat and require a skill in assaying therewith. On the other hand, glasses are different from the above-mentioned water-insoluble carriers in that immunologically active substances can be bound to them through covalent bonds and that immunologically active substances bound to glasses are stable and can be handled very easily. These products, however, still suffer from disadvantages in that quantity of an immunologically active substance that can be bound to a glass is small and therefore sensitivity and precision are not fully satisfactory and assay range is rather narrow.